Means for crush forming grinding wheels



c. w. KIRIN 2,458,605

MEANS FOR CRUSH FORMING GRINDING WHEELS I Jan. 11, 1949.

Filed Dec., 22, 1945 Fig.7 Fly 4 1G199 FiflO 3c lNVENTOR 29x14 CHARLES w K/R/N ATTORNEY Patented Jan. 11, 1949 UNITED STATESPATENT OFFICE MEANS FOR CRUSH FORMING GRINDING WHEELS 2 Claims.

This invention relates to the art of crush forming grinding wheels, wherein a specific contour is imparted to the periphery of a grinding wheel, which contour in turn is intended to be transferred toa work piece.

An object of the invention is the provision of means for crush forming grinding wheels which will greatly improve the method.

Another object of the invention is the provision of means for crush forming grinding wheels, whereby it is possible to obtain better pressure on the grinding wheel and better direction of the lines of force in the crushing operation.

Another object of the invention is the provision of means for crush form-ingpa grinding whee-l Where it is necessary to work in a limited space between the grinding wheel and the forming means.

Another object of the invention is the provision of a greatly simplified apparatus for 'crush iorm-' ing grinding wheels.

Another object of the invention is the provision of means for crush forming grin-ding wheels, wherein a multiplicity of forms may be placed on a single forming device.

Another object of the invention is the provision of means for crush forming grinding wheels in which the removal of the accumulation of grit and bond from the surfaces of the forming device and grinding wheel is greatly simplified.

The foregoing and other objects and advantages of the invention will become more apparent as the description proceeds, reference being made from time to time to the accompanying drawings forming part of the within disclosure, in which drawings:

Fig. 1 is a perspective view of a device embodying my invention.

Fig. 2 is an end View of the forming bar and grinding wheel illustrated in Fig. 1.

Figs. 3 to inclusive, illustrate end views of various modified forms of forming bars which may be employed in this method.

Figs. 11 and 12 illustrate perspective views of other modified forms of bars which may be employed in this method.

Fig. 13 is a perspective View of a fixture for supporting certain types of forming bars.

Fig. 14 is a top plan view of the bar illustrated in the fixture shown in Fig. 13.

Heretofore, it has been the practice in crush forming grinding Wheels to provide a forming wheel, on the periphery of which was formed the contour desired to be imparted to the grinding wheel. This method necessitated the provision of more or less complicated and bulky equipment for supporting and rotating the forming wheel in working relation with the grinding wheel.

I propose to utilize a flat forming bar in place of a wheel to crush form the grinding wheel. The length of the bar is preferably greater than the circumference of the wheel to be formed or dressed. My method has the following advantages over the previous method:

First, it permits the reduction and simplification of apparatus required to practice the method.

Second, it permits the placing of a multiplicity of contours, not neeessarily similar, on a single forming bar.

Third, it enables the easy removal of the particles of grit and bond which are broken away from the grinding wheel, by the use of a brush or compressed air hose.

Referring now more particularly to the drawings, it will be understood that in the embodiment herein disclosed, the reference character 21 indicates the base of a machine having tables 22, 23 and 24, the last two of which are longitudinally reciprocable with respect to one another by means of the rack 25, which engages a suitable pinion not shown, mounted on a shaft 28, which is controlled by the hand wheel 29.

The tables 23 and 24 are also laterally movable by suitable rack and pinion not shown, which is actuated by means of the shaft 26 and the hand wheel 21.

A back stand 30 is provided with adjustable spindle support 3|, which may be raised and lowered by means of a hand wheel 32. A spindle 33 supporting the grinding wheel 34, is mounted on the spindle support 3|.

The method herein described may be practiced on conventional surface grinders or similar devices, all of which is within the contemplation of the invention. A machine for crush forming and dressing grinding wheels can be constructed by duplicating a surface grinder, omitting the grinding wheel motor. Eliminating the base will provide a bench model.

A conventional magnetic chuck 35 is positioned on the table 24 and superimposed thereon is a forming bar 36, which has a contour 31, which is intended to be imparted to the grinding wheel 34 as at 38. A work piece 39 is positioned on the magnetic chuck adjacent to the forming bar 38. In order to crush form the grinding wheel, the tables 23 and 24 are adjusted laterally so that the forming bar 36 is in proper contacting position with the grinding wheel, and the wheel 34 is 3 lowered into contacting position with the forming bar 36 by means of the hand wheel 32.

Suflicient pressure is then exerted on the wheel 34 by the bar 36, to crush the abrasive particles and bond comprising the grinding wheel 34. The bar 36 is then reciprocated longitudinally by the longitudinal movement of the table 24 carrying the magnetic chuck 35, by means of hand wheel 29. As the bar is reciprocated, increasing pressures are exerted until the proper contour is imparted to the wheel. When the proper contour is formed on the wheel, the wheel is elevated a sufficient distance to clear the bar 36. The table 24 and the magnetic chuck 35 are then moved laterally so that the work piece 39 may be brought into alignment with the wheel 34, so that the contour 38 on the wheel 34 may then be imparted to the surface of the work piece 39.

Although I have shown the forming bar 36 in Fig. 1 as having a certain shape and contour, it will be understood that other shaped bars and contours may be employed in the same manner, end views of which are shown in Figs. 3 to 12. Figs. 9 and 10, respectively, illustrate concave and convex contours.

To support a convex forming bar, such as shown in Fig. 10, and to allow the use of the entire surface of the magnetic chuck, I have also devised a fixture, which may be mounted adjacent to the magnetic chuck. The fixture (Fig. 1), comprises a base plate 40, which may be secured to the table 24 by any suitable means, such as bolts 4|A adapted to engage the bolt holes 4 I.

The base plate 40 is provided with T slots 42, adapted to engage the T shaped clamps, not shown, carried on the underside of the supports 43, and are secured in place by bolts 44. The supports 43 are provided with cut out portions 45, corresponding to the contour of the forming bar intended to be employed in any particular operation. The end supports 43 and 43A are formed with lateral bores, which are adapted to engage reduced portions 430 formed on the end of the forming bar 46. The reduced portions 430 of the forming bar 46, are preferably threaded to accommodate locking nuts 43B at each end of the bar, which will prevent the displacement of the bar 46 from the fixture.

To crush form a wide grinding wheel or a gang of grinding wheels, a rectangular bar, as shown in Fig. 11, is used. The bar can be formed on both sides to provide two operative surfaces. This can also be accomplished by using individual forming bars, placed side by side as shown in Fig. 12, thus providing four operative surfaces.

Having described my invention, what I claim and desire to secure by Letters Patent is:

1. In a device of the character described, the combination of a grinding wheel, a longitudinally and laterally movable table below said grinding wheel, means on said table for supporting a forming bar having a contour intended to be imparted to said wheel, said means comprising a base having slots therein adjustable supports having cut out portions thereon adapted to accommodate the shape of said forming bar, and means cooperating between said slots and said supports for locking the latter in position on said base.

2. The combination defined in claim 1 in which at least one of said supports has means for preventing the longitudinal displacement of said forming bar.

CHARLES W. KIRIN.

REFERENCES CITED UNITED STATES PATENTS Name Date Bushwell Dec. 26, 1922 Number 

